I took some lessons with Agus when I first came to Bali. With his help I was very quickly able to learn enough of the language to get by: ordering food, haggling, asking for directions, all that sort of thing. A few more lessons and I was able to engage in simple conversations. And if I kept at it, I could probably learn to speak at a level good enough to impress the president!
Agus is well-educated and articulate, and has a very good knowledge of the intricacies of the Indonesian language. He also speaks very good English! He has also become a good friend, and his local knowledge of Bali has been very helpful. Bahasa Indonesian is a pretty easy language to learn, and if you plan on spending more than a few weeks in Bali I would recommend learning at least the basics.